From be691b5e593f2cc8cef67bbc59c1fb91b74a86a9 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Mon, 4 Nov 2024 07:26:33 +0100 Subject: [PATCH] btrfs: split bios to the fs sector size boundary Btrfs like other file systems can't really deal with I/O not aligned to it's internal block size (which strangely is called sector size in btrfs, for historical reasons), but the block layer split helper doesn't even know about that. Round down the split boundary so that all I/Os are aligned. Fixes: d5e4377d5051 ("btrfs: split zone append bios in btrfs_submit_bio") CC: stable@vger.kernel.org # 6.12 Reviewed-by: Johannes Thumshirn Signed-off-by: Christoph Hellwig Reviewed-by: Damien Le Moal Reviewed-by: David Sterba Signed-off-by: David Sterba --- fs/btrfs/bio.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) diff --git a/fs/btrfs/bio.c b/fs/btrfs/bio.c index 011cc97be3b5..78f5606baacb 100644 --- a/fs/btrfs/bio.c +++ b/fs/btrfs/bio.c @@ -649,8 +649,14 @@ static u64 btrfs_append_map_length(struct btrfs_bio *bbio, u64 map_length) map_length = min(map_length, bbio->fs_info->max_zone_append_size); sector_offset = bio_split_rw_at(&bbio->bio, &bbio->fs_info->limits, &nr_segs, map_length); - if (sector_offset) - return sector_offset << SECTOR_SHIFT; + if (sector_offset) { + /* + * bio_split_rw_at() could split at a size smaller than our + * sectorsize and thus cause unaligned I/Os. Fix that by + * always rounding down to the nearest boundary. + */ + return ALIGN_DOWN(sector_offset << SECTOR_SHIFT, bbio->fs_info->sectorsize); + } return map_length; } -- 2.49.0